Coating machine and coating method thereof

ABSTRACT

A coating machine and its coating method are provided. The coating machine includes: a cardboard conveying mechanism (1) with a front end (11) and a back end (12) higher than the front end (11); and a wax dispenser (2) provided above the back end (12) and provided with a wax dispensing roller (3) on each of two lateral sides of the wax dispenser (2). The coating machine and its coating method are designed to wax not only the surface, but also the edges, of cardboard (10) so that waterproofness of the entire cardboard (10) is ensured. The coating machine is structurally simple and highly automated, and the coating method is easy to perform and highly automated.

FIELD OF THE INVENTION

The present invention relates to a coating machine and a coating methodthereof. More particularly, the invention relates to a coating machineand method for use in the manufacture of cardboard boxes to coatheat-insulating cardboard with wax.

BACKGROUND OF THE INVENTION

Nowadays, marine products such as seafood are typically transported incardboard boxes. As liquids are sure to be found on the surface ofseafood, it is required that cardboard boxes for storing marine productsbe water-resistant to some extent so that boxed marine products can betransported over long distances.

To waterproof a cardboard box, it is common practice to coat each of itscardboard components with liquid wax, which forms a wax layer capable ofisolating the surface liquids of marine products from the cardboarditself. However, the existing coating machines can effectively coat onlythe surface, but not the edges, of cardboard with wax. The resultingcardboard boxes, therefore, are flawed in that they are permeable towater and hence prone to break when wet.

To overcome the foregoing drawback, a novel coating machine for forminga wax layer on cardboard is needed.

BRIEF SUMMARY OF THE INVENTION

One objective of the present invention is to provide a coating machinethat is structurally simple, highly automated, and capable of waxing notonly the surface, but also the edges, of cardboard so thatwaterproofness of the entire cardboard is ensured.

Another objective of the present invention is to provide a coatingmethod that is easy to perform, highly automated, and capable of waxingnot only the surface, but also the edges, of cardboard so thatwaterproofness of the entire cardboard is ensured.

The above objectives can be achieved by the following technicalsolutions:

The present invention provides a coating machine that includes acardboard conveying mechanism and a wax dispenser.

The cardboard conveying mechanism has a front end and a back end,wherein the front end is lower than the back end.

The wax dispenser is provided above the back end and is provided with awax dispensing roller on each of two lateral sides of the wax dispenser.

Preferably, each of the wax dispensing rollers includes a roller bodyand a felt sleeve.

Each roller body has a hollow chamber in communication with the waxdispenser through a connecting tube and is provided with a plurality ofthrough holes in communication with the hollow chamber.

Each felt sleeve is mounted around the corresponding roller body.

Preferably, the cardboard conveying mechanism includes a conveyor bodyand a plurality of pressure rollers.

The conveyor body has a front-end conveying wheel, a back-end conveyingwheel, and a conveyor belt looped around the front-end conveying wheeland the back-end conveying wheel. Cardboard can be placed on theconveyor belt in order to be coated.

The pressure rollers are provided above the conveyor body such thatcardboard can be held between the conveyor belt and the pressurerollers.

Preferably, the coating machine further includes a wax trough below thewax dispenser and the two wax dispensing rollers.

Preferably, the front end of the cardboard conveying mechanism isprovided with a cardboard holder, and the cardboard holder has aninclined cardboard-supporting table.

Preferably, the back end of the cardboard conveying mechanism isprovided with a transport mechanism that includes a front-end transportwheel, a middle transport wheel, and a rear-end transport wheel. Boththe front-end transport wheel and the rear-end transport wheel are lowerthan the middle transport wheel. A first transport belt is looped aroundthe front-end transport wheel and the middle transport wheel while asecond transport belt is looped around the middle transport wheel andthe rear-end transport wheel.

Preferably, the rear-end transport wheel is lower than the front-endtransport wheel.

Preferably, a cardboard collector is provided near the rear-endtransport wheel.

Preferably, the coating machine further includes a wax reservoir forstoring liquid wax. The wax reservoir is connected to the wax dispenserthrough a pump and is below the wax trough.

The present invention also provides the coating method of the foregoingcoating machine, wherein the coating method includes the steps of:

a) placing cardboard on the cardboard conveying mechanism such that thewax dispenser is vertically aligned with a forward edge of thecardboard;

b) turning on the wax dispenser and the cardboard conveying mechanism inorder for the wax dispenser to dispense wax to the forward edge and anupper surface of the cardboard; and

c) coating two lateral edges of the cardboard with wax by the waxdispensing rollers on the two lateral sides of the wax dispenserrespectively while the cardboard is moved from the front end of thecardboard conveying mechanism to the back end of the cardboard conveyingmechanism.

It is preferable that the cardboard is heat-insulating cardboard, thatthe heat-insulating cardboard includes a cardboard body and aheat-insulating material adhesively bonded to each other, and that anouter surface of the cardboard body as well as two lateral edges and aforward edge of the heat-insulating cardboard is to be coated with wax.

It is preferable that the cardboard body is 0.3 mm-9 mm thick.

It is preferable that the heat-insulating material is 1 mm-6 mm thick.

The coating machine and coating method of the present invention have thefollowing features and advantages: The two wax dispensing rollers canwax two lateral edges of a sheet of cardboard respectively while the waxdispenser dispenses wax evenly over the upper surface and forward edgeof the cardboard, and this effectively ensures that the coated cardboardis waterproofed as a whole. Aside from being able to wax an entire sheetof cardboard, the invention is structurally simple, easy to perform, andhighly automated.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

To expound the technical solutions provided by embodiments of thepresent invention, a brief description of the accompanying drawings, towhich the following embodiments refer, is given below. It is understoodthat the accompanying drawings show only some embodiments of theinvention, and that a person of ordinary skill in the art may deriveother drawings from the accompanying ones without creative labor.

FIG. 1 schematically shows the structure of a coating machine accordingto the present invention.

FIG. 2 schematically shows the structure of a wax dispensing roller ofthe coating machine in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

The technical solutions provided by embodiments of the present inventionare detailed below with reference to the accompanying drawings. It isunderstood that the embodiments described herein are only someillustrative ones, and do not include all the possible embodiments, ofthe invention. All other embodiments achievable by a person of ordinaryskill in the art without creative labor should fall within the scope ofpatent protection sought by the present applicant.

Embodiment 1

As shown in FIG. 1, the present invention provides a coating machinethat includes a cardboard conveying mechanism 1 and a wax dispenser 2.The cardboard conveying mechanism 1 has a front end 11 and a back end12, wherein the front end 11 is lower than the back end 12. The waxdispenser 2 is provided above the back end 12, and a wax dispensingroller 3 is provided on each of two lateral sides of the wax dispenser2.

More specifically, the cardboard conveying mechanism 1 includes aconveyor body 4 and a plurality of pressure rollers 5. The conveyor body4 has a front-end conveying wheel 41, a back-end conveying wheel 42, anda conveyor belt 43 looped around the front-end conveying wheel 41 andthe back-end conveying wheel 42. Cardboard 10 can be placed on theconveyor belt 43 in order to be coated. The cardboard 10 may be asingle- or multi-ply composite cardboard having a thickness ranging from0.3 mm to 9 mm; the present invention has no limitation in this regard.The pressure rollers 5 are provided above the conveyor body 4 in such away that the cardboard 10 can be held between the conveyor belt 43 andthe pressure rollers 5.

The wax dispenser 2 is located above the back end 12 of the cardboardconveying mechanism 1 and has a wax outlet 21 lying above the back-endconveying wheel 42 of the cardboard conveying mechanism 1. The waxoutlet 21 of the wax communication with the wax dispenser 2 through aconnecting tube 33. The roller body 31 is also provided with a pluralityof through holes 311 in communication with the hollow chamber. The feltsleeve 32 is mounted around the roller body 31.

More specifically, the wax dispensing roller 3 has a fixing frame 34.The roller body 31 is rotatably connected to the fixing frame 34 viabearings provided respectively at two ends of the roller body 31. Theroller body 31 is generally cylindrical and has its upper end connectedto the wax dispenser 2 through the connecting tube 33 in order for theliquid wax in the wax dispenser 2 to flow through the connecting tube 33into the hollow chamber of the roller body 31. The through holes 311 areprovided in the peripheral wall of the roller body 31 and are incommunication with the hollow chamber so that the liquid wax flowinginto the hollow chamber of the roller body 31 can flow through thethrough holes 311 to the outer surface of the roller body 31.

The felt sleeve 32 is generally cylindrical, has an inner diameterslightly larger than the outer diameter of the roller body 31, and ismounted around the outer surface of the roller body 31 so as to rotatealong with the roller body 31. While the roller body 31 is rotated, thefelt sleeve 32 is in contact with the outer surface of the roller body31 and can also contact the corresponding lateral edge of the cardboard10, thereby dispensing the liquid wax on the outer surface of the rollerbody 31 to (i.e., waxing) the corresponding lateral edge of thecardboard 10.

The coating machine further includes a wax trough 8 below the waxdispenser 2 and the two wax dispensing rollers 3 in order to collectexcess liquid wax flowing out of the wax dispenser 2 and the waxdispensing rollers 3. The wax trough 8 lies above the wax reservoir 7,and the liquid wax in the wax trough 8 can flow into the wax reservoir 7through an outlet at the bottom of the wax trough 8.

In this embodiment of the present invention, the front end 11 of thecardboard conveying mechanism 1 is provided with a cardboard holder 13.The cardboard holder 13 has an inclined cardboard-supporting table 131on which to place the cardboard 10 to be waxed and that facilitatesconveyance of the cardboard 10 by giving the cardboard 10 the sameinclination angle as the conveyor belt 43 before the cardboard 10 is fedinto the cardboard conveying mechanism 1.

Moreover, the back end 12 of the cardboard conveying mechanism 1 isprovided with a transport mechanism 9. The transport mechanism 9includes a front-end transport wheel 91, a middle transport wheel 92,and a rear-end transport wheel 93. Both the front-end transport wheel 91and the rear-end transport wheel 93 are lower than the middle transportwheel 92. A first transport belt 94 is looped around the front-endtransport wheel 91 and the middle transport wheel 92 while a secondtransport belt 95 is looped around the middle transport wheel 92 and therear-end transport wheel 93. In this embodiment, the rear-end transportwheel 93 is lower than the front-end transport wheel 91.

Once turned on, the front-end transport wheel 91, the middle transportwheel 92, and the rear-end transport wheel 93 of the transport mechanism9 are rotated such that the first transport belt 94 receives thecurtain-coated cardboard 10 from the cardboard conveying mechanism 1 andtransports the cardboard 10 to the second transport belt 95, whichfurther transports the cardboard 10 to a cardboard collector 96 near therear-end transport wheel 93 to complete collection of the waxedcardboard 10.

The coating machine of the present invention is so designed that notonly can the wax dispenser 2 coat the upper surface and forward edge ofthe cardboard 10 evenly with wax, but also the two wax dispensingrollers 3 can wax the two lateral edges of the cardboard 10 respectivelyto ensure that the cardboard 10 is waterproofed as a whole. In additionto the ability to wax the entire cardboard 10, the coating machinefeatures a simple structure and a high degree of automation.

Embodiment 2

With continued reference to FIG. 1 and FIG. 2, the present inventionfurther provides the coating method of a coating machine. Thestructures, working principle, and advantageous effects of the coatingmachine in embodiment 2 are identical to those of the coating machine inembodiment 1 and hence will be not be described repeatedly. The coatingmethod of the coating machine includes the following steps:

a) Place the cardboard 10 on the cardboard conveying mechanism 1, withthe wax dispenser 2 in vertical alignment with the forward edge of thecardboard 10;

b) Turn on the wax dispenser 2 and the cardboard conveying mechanism 1so that the wax dispenser 2 dispenses wax to the forward edge and theupper surface of the cardboard 10; and

c) Wax the two lateral edges of the cardboard 10 with the wax dispensingrollers 3 on the two lateral sides of the wax dispenser 2 respectivelywhile the cardboard 10 is moved from the front end 11 of the cardboardconveying mechanism 1 to the back end 12 of the cardboard conveyingmechanism 1.

More specifically, the cardboard conveying mechanism 1 is inclined at acertain angle such that the cardboard 10 placed thereon is inclined atthe same angle.

Once turned on, the front-end conveying wheel 41 and the back-endconveying wheel 42 of the cardboard conveying mechanism 1 are rotatedand thereby move the cardboard 10 from the front end 11 to the back end12 of the cardboard conveying mechanism 1 via the conveyor belt 43. Asthe cardboard 10 is conveyed slantingly upward, the liquid wax in thewax dispenser 2 above the back end 12 falls as a curtain on the forwardedge of the cardboard 10, and constant-speed movement of the cardboard10 along the cardboard conveying mechanism 1 allows the liquid waxfalling from the wax dispenser 2 to also curtain-coat the entire uppersurface of the cardboard 10. Consequently, the upper surface as well asthe forward edge of the cardboard 10 is evenly coated with liquid wax.It is worth mentioning that, during the conveying process, the pressurerollers 5 above the cardboard conveying mechanism 1 hold the cardboard10 against the conveyor belt 43 to prevent the cardboard 10 from slidingoff the conveyor belt 43.

In the present invention, the cardboard 10 is heat-insulating cardboardthat includes a cardboard body and a heat-insulating material adhesivelybonded to each other. The liquid wax falling from the wax dispenser 2can curtain-coat the outer surface of the cardboard body and the forwardedge of the heat-insulating cardboard, and each of the two lateral edgesof the heat-insulating cardboard can be coated by the wax dispensingroller 3 on one of the two lateral sides of the wax dispenser 2. In thepresent invention, the cardboard body has a thickness of 0.3 mm˜9 mm,and the heat-insulating material has a thickness of 1 mm˜6 mm.

The coating method of the present invention not only dispenses wax tothe upper surface and forward edge of the cardboard 10, but also waxesthe two lateral edges of the cardboard 10 to effectively ensurewaterproofness of the entire cardboard 10. Aside from being capable ofwaxing the whole cardboard 10, the coating method is easy to perform andfeatures a high degree of automation.

The foregoing is only a couple of embodiments of the present invention.A person skilled in the art may modify or change the disclosedembodiments in many ways according to the disclosure of the presentspecification without departing from the scope of the invention.

What is claimed is:
 1. A coating machine, characterized by comprising: acardboard conveying mechanism having a front end and a back end, whereinthe front end is lower than the back end; and a wax dispenser providedabove the back end and provided with a wax dispensing roller on each oftwo lateral sides of the wax dispenser.
 2. The coating machine of claim1, characterized in that each of the wax dispensing rollers comprises: aroller body having a hollow chamber in communication with the waxdispenser through a connecting tube, the roller body being provided witha plurality of through holes in communication with the hollow chamber,and a felt sleeve mounted around the roller body.
 3. The coating machineof claim 1, characterized in that the cardboard conveying mechanismcomprises: a conveyor body having a front-end conveying wheel, aback-end conveying wheel, and a conveyor belt looped around thefront-end conveying wheel and the back-end conveying wheel such thatcardboard is placeable on the conveyor belt in order to be coated; and aplurality of pressure rollers provided above the conveyor body such thatthe cardboard is able to be held between the conveyor belt and thepressure rollers.
 4. The coating machine of claim 1, characterized byfurther comprising a wax trough below the wax dispenser and the two waxdispensing rollers.
 5. The coating machine of claim 1, characterized inthat the front end of the cardboard conveying mechanism is provided witha cardboard holder, and that the cardboard holder has an inclinedcardboard-supporting table.
 6. The coating machine of claim 1,characterized in that the back end of the cardboard conveying mechanismis provided with a transport mechanism; that the transport mechanismcomprises a front-end transport wheel, a middle transport wheel, and arear-end transport wheel; that the front-end transport wheel and therear-end transport wheel are lower than the middle transport wheel; andthat there are a first transport belt looped around the front-endtransport wheel and the middle transport wheel and a second transportbelt looped around the middle transport wheel and the rear-end transportwheel.
 7. The coating machine of claim 6, characterized in that therear-end transport wheel is lower than the front-end transport wheel. 8.The coating machine of claim 6, characterized in that a cardboardcollector is provided near the rear-end transport wheel.
 9. The coatingmachine of claim 4, characterized by further comprising a wax reservoirfor storing liquid wax, wherein the wax reservoir is connected to thewax dispenser through a pump and is below the wax trough.
 10. A coatingmethod of the coating machine of claim 1, characterized by comprisingthe steps of: a) placing the cardboard on the cardboard conveyingmechanism such that the wax dispenser is vertically aligned with aforward edge of the cardboard; b) turning on the wax dispenser and thecardboard conveying mechanism in order for the wax dispenser to dispensewax to the forward edge and an upper surface of the cardboard; and c)coating two lateral edges of the cardboard with wax by the waxdispensing rollers on the two lateral sides of the wax dispenserrespectively while the cardboard is moved from the front end of thecardboard conveying mechanism to the back end of the cardboard conveyingmechanism.
 11. A coating method of the coating machine of claim 2,characterized by comprising the steps of: a) placing the cardboard onthe cardboard conveying mechanism such that the wax dispenser isvertically aligned with a forward edge of the cardboard; b) turning onthe wax dispenser and the cardboard conveying mechanism in order for thewax dispenser to dispense wax to the forward edge and an upper surfaceof the cardboard; and c) coating two lateral edges of the cardboard withwax by the wax dispensing rollers on the two lateral sides of the waxdispenser respectively while the cardboard is moved from the front endof the cardboard conveying mechanism to the back end of the cardboardconveying mechanism.
 12. A coating method of the coating machine ofclaim 3, characterized by comprising the steps of: a) placing thecardboard on the cardboard conveying mechanism such that the waxdispenser is vertically aligned with a forward edge of the cardboard; b)turning on the wax dispenser and the cardboard conveying mechanism inorder for the wax dispenser to dispense wax to the forward edge and anupper surface of the cardboard; and c) coating two lateral edges of thecardboard with wax by the wax dispensing rollers on the two lateralsides of the wax dispenser respectively while the cardboard is movedfrom the front end of the cardboard conveying mechanism to the back endof the cardboard conveying mechanism.
 13. A coating method of thecoating machine of claim 4, characterized by comprising the steps of: a)placing the cardboard on the cardboard conveying mechanism such that thewax dispenser is vertically aligned with a forward edge of thecardboard; b) turning on the wax dispenser and the cardboard conveyingmechanism in order for the wax dispenser to dispense wax to the forwardedge and an upper surface of the cardboard; and c) coating two lateraledges of the cardboard with wax by the wax dispensing rollers on the twolateral sides of the wax dispenser respectively while the cardboard ismoved from the front end of the cardboard conveying mechanism to theback end of the cardboard conveying mechanism.
 14. A coating method ofthe coating machine of claim 5, characterized by comprising the stepsof: a) placing the cardboard on the cardboard conveying mechanism suchthat the wax dispenser is vertically aligned with a forward edge of thecardboard; b) turning on the wax dispenser and the cardboard conveyingmechanism in order for the wax dispenser to dispense wax to the forwardedge and an upper surface of the cardboard; and c) coating two lateraledges of the cardboard with wax by the wax dispensing rollers on the twolateral sides of the wax dispenser respectively while the cardboard ismoved from the front end of the cardboard conveying mechanism to theback end of the cardboard conveying mechanism.
 15. A coating method ofthe coating machine of claim 6, characterized by comprising the stepsof: a) placing the cardboard on the cardboard conveying mechanism suchthat the wax dispenser is vertically aligned with a forward edge of thecardboard; b) turning on the wax dispenser and the cardboard conveyingmechanism in order for the wax dispenser to dispense wax to the forwardedge and an upper surface of the cardboard; and c) coating two lateraledges of the cardboard with wax by the wax dispensing rollers on the twolateral sides of the wax dispenser respectively while the cardboard ismoved from the front end of the cardboard conveying mechanism to theback end of the cardboard conveying mechanism.
 16. The coating method ofclaim 10, characterized in that the cardboard is heat-insulatingcardboard, that the heat-insulating cardboard comprises a cardboard bodyand a heat-insulating material adhesively bonded to each other, and thatan outer surface of the cardboard body as well as two lateral edges anda forward edge of the heat-insulating cardboard is to be coated withwax.
 17. The coating method of claim 11, characterized in that thecardboard is heat-insulating cardboard, that the heat-insulatingcardboard comprises a cardboard body and a heat-insulating materialadhesively bonded to each other, and that an outer surface of thecardboard body as well as two lateral edges and a forward edge of theheat-insulating cardboard is to be coated with wax.
 18. The coatingmethod of claim 12, characterized in that the cardboard isheat-insulating cardboard, that the heat-insulating cardboard comprisesa cardboard body and a heat-insulating material adhesively bonded toeach other, and that an outer surface of the cardboard body as well astwo lateral edges and a forward edge of the heat-insulating cardboard isto be coated with wax.
 19. The coating method of claim 13, characterizedin that the cardboard is heat-insulating cardboard, that theheat-insulating cardboard comprises a cardboard body and aheat-insulating material adhesively bonded to each other, and that anouter surface of the cardboard body as well as two lateral edges and aforward edge of the heat-insulating cardboard is to be coated with wax.20. The coating method of claim 14, characterized in that the cardboardis heat-insulating cardboard, that the heat-insulating cardboardcomprises a cardboard body and a heat-insulating material adhesivelybonded to each other, and that an outer surface of the cardboard body aswell as two lateral edges and a forward edge of the heat-insulatingcardboard is to be coated with wax.
 21. The coating method of claim 15,characterized in that the cardboard is heat-insulating cardboard, thatthe heat-insulating cardboard comprises a cardboard body and aheat-insulating material adhesively bonded to each other, and that anouter surface of the cardboard body as well as two lateral edges and aforward edge of the heat-insulating cardboard is to be coated with wax.22. The coating method of claim 16, characterized in that the cardboardbody has a thickness of 0.3 mm˜9 mm.
 23. The coating method of claim 17,characterized in that the cardboard body has a thickness of 0.3 mm˜9 mm.24. The coating method of claim 18, characterized in that the cardboardbody has a thickness of 0.3 mm˜9 mm.
 25. The coating method of claim 19,characterized in that the cardboard body has a thickness of 0.3 mm˜9 mm.26. The coating method of claim 20, characterized in that the cardboardbody has a thickness of 0.3 mm˜9 mm.
 27. The coating method of claim 21,characterized in that the cardboard body has a thickness of 0.3 mm˜9 mm.28. The coating method of claim 16, characterized in that theheat-insulating material has a thickness of 1 mm˜6 mm.
 29. The coatingmethod of claim 17, characterized in that the heat-insulating materialhas a thickness of 1 mm˜6 mm.
 30. The coating method of claim 18,characterized in that the heat-insulating material has a thickness of 1mm˜6 mm.
 31. The coating method of claim 19, characterized in that theheat-insulating material has a thickness of 1 mm˜6 mm.
 32. The coatingmethod of claim 20, characterized in that the heat-insulating materialhas a thickness of 1 mm˜6 mm.
 33. The coating method of claim 21,characterized in that the heat-insulating material has a thickness of 1mm˜6 mm.